A comprehensive neuropsychological test battery has been devised to provide a complete assessment of various cognitive functions which can be related to damage or dysfunction in different regions of the brain. The battery comprises tests designed to tap the following aspects of behavior: executive functions, language, vigilance (attention), visual-spatial capacity, memory, motor behavior and auditory functioning. In addition, measures of psychometric intelligence, personality, color vision and hand and eye dominance are included. The intent of developing the battery is to provide an archival assessment of the neurobehavioral capacities of the various subgroups of patients who are studied by investigators within the LPP; although, eventually, administration of the battery may be extended to all IRP patients. The data can thus provide a complete behavioral assessment against which to relate the neurophysiological, neuroradiological and biochemical information that is gathered concurrently on these patients. The data will be included in the permanent file of each patient and should provide eventual actuarial summarization of cognitive and perceptual functions for the different clinical populations that have been studied in the IRP and facilitate research relating to behavioral factors in neuro- and psychopathology.